Swales

Swales are shallow, gently sloped trenches that channel water runoff away from heavy-use areas. Swales are commonly planted with grass, which slows down runoff, facilitates infiltration and removes sediment and other particles. Swales can be easily incorporated into the landscape on residential property, particularly if there is already a low lying area on the property.

Swales should be designed to hold water for no more than 48 to 72 hours to reduce habitat for mosquitoes. Grass height should be maintained at no less than 3- 4 inches tall to provide adequate erosion protection. Bare or eroded spots should be repaired and reseeded. The swale should not be used as a track or roadway. Frequent traffic may damage the swale and create ruts, which can concentrate water flow and eventually result in erosion and the formation of gullies.